Map ideas for MODs or an official expansion pack:
A dogfighting map. A droid controller ship on one side, a Republic "mini-star-destroyer" on the other, each with bays to spawn pilots and launch fighters into the void. You could even use a water cube to encompass the entire area in between the bays so that if you jump out of your ship while in space, you die.
Eradicate the enemy, or board and capture the enemy ship — that fits the gamplay mechanic. Would work similarly well during the fleet battle around Endor with ISDs and Calimari cruisers.
A gungan city map. A whole bunch of those underwater shield bubble things we see in Ep1 for a Kamino/Bespin platforms style map. Droiddeka can't survive underwater, so they'd be limited to connective passages filled with air; other troops would be able to use bongos to move between bubbles safely, or risk a quick run between the bubbles at the cost of health while exposed to water. An Opee Seakiller would be a nice replacement for a Sarlaac on this sort of map too...
Geonosis Droid Foundary interior as a Bespin City type skirmish map. We didn't see any fighting in there in the movies, but then again, there wasn't any fighting on Kamino either (AND the battle could have easily carried on down into the foundary during the "Assembly area" battle.)
A Geonosis Arena map could easily be set up like the Yavin Temple, with command points on either side of the arena bowl and others in the arena wall honeycombs. The arena critters would make for some really neat environmental hazards too...
(Kind of like hero units, but for the "native" faction so that they attack both Clones and Geonosians/Droids.)